JP4761369B2 - Bending machine - Google Patents

Description

  The present invention relates to a bending apparatus for automatically bending a straight pipe into a three-dimensional bending shape.

  Conventionally, for example, a bending apparatus as shown in Patent Document 1 below is known. This conventional bending apparatus includes a retracting mechanism that retracts a chuck mechanism that can grip a long workpiece (pipe) from the axis of the pipe. In addition, this conventional bending apparatus includes two sets of moving mechanisms that move in parallel with the pipe held by the chuck mechanism and on two sets of tracks provided on both sides of the chuck mechanism toward the chuck mechanism. An articulated robot in which a bending mechanism for bending a pipe is assembled is mounted on the moving mechanism.

In the conventional bending apparatus configured as described above, the chuck mechanism grips a long pipe, and two sets of moving mechanisms move the articulated robot toward the chuck mechanism. Then, the articulated robot uses the joint to rotate the bending mechanism assembled at the tip around the axis of the pipe so that a predetermined bending direction is obtained. Thereby, the bending mechanism bends the pipe into a predetermined bending shape three-dimensionally. Further, the retracting mechanism retracts the chuck mechanism from the axis of the pipe, so that interference between the chuck mechanism and the bending mechanism can be avoided. Thus, by avoiding interference between the chuck mechanism and the bending mechanism, it is possible to reduce an area where bending cannot be performed (an area where bending is impossible) when these mechanisms interfere with each other.
Japanese Patent Publication No. 5-13011

  However, although the conventional bending apparatus can be bent until just before the two articulated robots come into contact with each other, the minimum bendable area at this time is between the arm side surface of the articulated robot and the bending mold center of the bending mechanism. The distance is approximately twice the distance. Actually, from the viewpoint of ensuring the accuracy of the bending process, it is necessary to perform an accurate bending process even after the chuck mechanism is retracted. When the unbendable area increases in this way, there is a high possibility that the unbendable area must be bent. In this case, a separate bending process is set, and the long pipe, which has already been partially bent, is removed from the conventional bending apparatus and set in a separately prepared bending apparatus or bending mold. Bending must be processed. In this way, in particular, when detaching a long pipe between bending devices, the product shape such as unnecessary deformation in the already bent part or time for detaching the pipe is required. There is a problem that the molding accuracy is lowered and the productivity is deteriorated.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a bending apparatus that can greatly reduce a non-bendable region when a predetermined bending shape is processed on a pipe. .

  The present invention is characterized in that a chuck unit comprising a chuck mechanism capable of gripping a straight pipe and a retracting mechanism for retracting the chuck mechanism from the axis of the pipe, and provided on both sides of the chuck unit, In a bending apparatus comprising a pair of bending units comprising a bending mechanism that bends a predetermined bending shape and a moving mechanism that moves the bending mechanism connected via a support member in the axial direction of the pipe. A head chuck mechanism for gripping the pipe in response to retraction of the chuck mechanism of the chuck unit is provided for one bending unit of the pair of bending units; An insertion hole through which the head chuck mechanism is inserted into the support member of the other bending unit is provided in the pie. It lies in the axis and coaxially formed of.

  In this case, a head retracting mechanism for retracting the bending mechanism from the axis of the pipe is further provided for the one bending processing unit, and the one bending processing unit is provided with the bending mechanism by the head retracting mechanism. After the retraction, the moving mechanism may move the bending mechanism toward the bending position of the pipe bent before retraction, and the pipe may be gripped near the bending position by the head chuck mechanism.

  Further, in these cases, the head chuck mechanism is housed in the outer case having a substantially U-shaped cross section perpendicular to the axial direction of the pipe, and is supplied from the outside. A diaphragm that expands and contracts in response to the pressure of the air to be moved, and a clamp that holds the pipe as the diaphragm expands and opens the pipe as the diaphragm contracts.

  In the bending apparatus of the present invention configured as above, first, when a straight pipe is supplied, the pipe is gripped by the chuck mechanism of the chuck unit. Then, the bending units provided on both sides of the chuck unit respectively move to both end positions of the pipe gripped by the moving mechanism. In this way, each of the moved bending units sequentially processes a predetermined bent shape from the both end positions of the pipe toward the central position of the pipe.

  When these bending units approach the chuck unit along with the bending by the respective bending units, the gripping of the pipe by the chuck mechanism of the chuck unit is released and the chuck mechanism is retracted from the axis of the pipe. Then, the pipe is gripped by the head chuck mechanism provided in one bending unit in accordance with the release and retraction of the grip by the chuck unit. Here, in a state where the head chuck mechanism is holding the pipe, the bending process and the movement in the axial direction of one bending process unit are stopped. Thus, in a state where the head chuck mechanism properly holds the pipe, the other bending unit continues to process the bent shape with respect to the pipe. When the respective bending units are close to each other, the head chuck mechanism passes through the insertion hole provided in the support member of the other bending unit, so that the other bending unit is moved to the vicinity of the head chuck mechanism. Bending.

  Therefore, it is possible to reduce the unbendable region that occurs when the bending units approach each other. In other words, the region where bending can be performed (bendable region) can be expanded. Thereby, for example, the number of times of detaching / attaching the pipe can be greatly reduced, the molding accuracy of the product shape can be maintained, and the productivity can be improved.

  Further, when the head retracting mechanism for retracting the bending mechanism from the axis of the pipe is provided in one bending unit, the unbendable region can be further reduced. That is, when the head chuck mechanism grips the pipe, the bending mechanism is retracted by the head retracting mechanism. Then, after moving in the direction of the bending position where the bending mechanism is retracted, the head chuck mechanism grips the vicinity of the processing position. As described above, the other bending unit is bent to the vicinity of the head chuck mechanism as described above in the state where the head chuck mechanism has gripped the vicinity of the processing position where the bending has already been performed. Can be made smaller. Therefore, the bendable area can be greatly expanded, and the productivity can be greatly improved. In addition, by retracting the bending mechanism of one bending unit, it is possible to prevent interference between the bending part and the bending mechanism, thereby maintaining good molding accuracy of the product shape. You can also.

  Further, the head chuck mechanism can be reduced in size by configuring the head chuck mechanism with a diaphragm and a clamp housed in the outer case. That is, the expansion direction of the diaphragm due to the air pressure can be regulated inward of the outer case, and the movable range associated with the gripping or opening of the pipe by the head chuck mechanism can be within the outer dimension of the outer case. Thereby, the head chuck mechanism can be reduced in size very easily, the insertion hole formed in the other support member can also be reduced, and the bending apparatus itself can be reduced in size.

  The head chuck mechanism can grip the pipe by the expansion of the diaphragm. As a result, the force for gripping the pipe (so-called clamping force) can be appropriately changed as appropriate by adjusting the pressure of the air supplied to the diaphragm. As a result, the pipe can be gripped with an appropriate clamping force. As a result, unnecessary movement of the pipe during bending can be suppressed, and the forming accuracy can be maintained well.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 schematically shows a bending apparatus M according to the present invention. The bending apparatus M includes a center chuck unit 10 erected on the base B, and a pair of left and right first bending units 20 and second bending units 30 disposed on both sides of the center chuck unit 10. It is configured.

  The center chuck unit 10 includes a chuck mechanism 11 that is disposed coaxially with the axis of the straight tubular pipe P, and a cylinder 12 that serves as a retracting mechanism for retracting the chuck mechanism 11 from the axis of the pipe P. . The chuck mechanism 11 has a plurality of (for example, two) chuck claws, and grips the outer periphery of the pipe P by the chuck claws. As for the detailed structure of the chuck mechanism 11, a well-known structure can be adopted, and since it is not directly related to the present invention, detailed description is omitted. For example, the cylinder 12 expands and contracts by supplying or discharging hydraulic pressure or air pressure, and raises or lowers the chuck mechanism 11.

  The first bending unit 20 (also simply referred to as the processing unit 20 in the following description) includes two sets of rails R installed on the upper surface of the base B so as to be parallel to the axial direction of the straight pipe P. Among these, a moving table 21 is provided that moves in the left-right direction on a set of rails provided on the far side in the vertical direction of the drawing in FIG. A feed motor 22 for moving the platform 21 and a stand 23 as a support member are assembled on the movable platform 21. For example, a servo motor may be employed as the feed motor 22. In the stand 23, an insertion hole 23a for inserting a head chuck 40 assembled in a second bending unit 30 described later is coaxial with the axis of the pipe P gripped by the center chuck unit 10 or the head chuck 40. Formed as follows. Here, the movable table 21 and the feed motor 22 constitute the feed mechanism of the present invention.

  Above the stand 23, a bending die 24, a bending motor 25, and a twisting motor 26 that form a bending mechanism for bending the pipe P based on a predetermined feed amount, a twisting angle, and a bending angle are assembled. . As for the configuration and operation of the bending die 24, the bending motor 25, and the twisting motor 26 that form the bending mechanism, for example, a well-known configuration is employed as disclosed in Japanese Patent No. 3865526. In addition, since it is not directly related to the present invention, it will be briefly described below.

  The bending die 24 includes a fixed roll and a bending roller that is rotatable along the outer periphery of the fixed roll, and a caliber that holds the pipe P is formed on each of the fixed roll and the bending roller. . Note that the fixed roll and the bending roller can be switched between an approaching state and a separating state, and when the pipe P is bent with respect to the pipe P, the fixing roll and the bending roller approach each other and hold the pipe P with a caliber. When the straight pipe P is set or removed after bending, the pipes P are separated from each other to be released from the caliber.

  The bending motor 25 is connected to the bending roller via a predetermined speed reduction mechanism, and the bending roller is rotated along the outer periphery of the fixed roll by the driving force of the bending motor 25. The bending motor 25 may be a servo motor, for example. The bending die 24 and the bending motor 25 are attached to the stand 23 via the twist plate 27. The twist plate 27 is assembled to the stand 23 so as to be rotatable around the axis of the pipe P gripped by the center chuck unit 10 or the head chuck 40, and is connected to the twist motor 26 via a pulley, a gear, and a predetermined reduction mechanism. Has been. The twist motor 26 may be a servo motor, for example.

  With this configuration, when the twisting motor 26 is driven, the twisting plate 27 can be rotated 360 ° around the axis of the pipe P. As the twisting plate 27 rotates, the bending mold 24 and the bending motor 25 are also connected to the pipe P. Can rotate around the axis. When the bending motor 25 is driven in a state where the bending die 24 and the bending motor 25 are rotated by a predetermined twist angle, the bending roller of the bending die 24 rotates along the outer periphery of the fixed roller. Accordingly, a predetermined three-dimensional bent shape can be formed on the pipe P.

  On the other hand, the second bending unit 30 (also simply referred to as the processing unit 30 in the following description) is configured in substantially the same manner as the processing unit 20. That is, the second bending unit 30 moves in the left-right direction on one set of rails provided on the front side in the vertical direction of the paper in FIG. 1 among the above-described two sets of rails installed on the upper surface of the base B. A moving table 31 is provided. A feed motor 32 and a stand 33 are assembled on the moving table 31. A bending die 34, a bending motor 35, a twisting motor 36 and a twisting plate 37 are assembled above the stand 33 via a support plate 38.

  The support plate 38 is provided so as to be displaceable with respect to the vertical direction of the stand 33, and moves according to the expansion and contraction of the head cylinder 39 connected below. That is, by extending the head cylinder 39, the bending die 34 can bend and process the pipe P with the caliber therebetween. Further, by reducing the head cylinder 39, the bending die 34, the bending motor 35, the twisting motor 36 and the twisting plate 37 can be integrally moved downward. The support plate 38 and the head cylinder 39 constitute the head retracting mechanism of the present invention.

  Further, in the second bending unit 30, after the center chuck unit 10 is retracted, the head chuck 40 that grips the pipe P is integrally assembled to the stand 33. As shown in FIG. 2, the head chuck 40 includes an outer case 41 having a substantially U-shaped cross section and a pair of diaphragms 43 accommodated in the case 41 via an inner case 42. The outer case 41 is assembled to the stand 33 so that the opening end side having a substantially U-shaped cross section faces upward of the bending apparatus M. Each diaphragm 43 is connected to a pipe H for supplying air from the outside (for example, an air compressor) and exhausting the supplied air.

  Further, the diaphragm 43 has a shape substantially the same as the outer peripheral shape of the pipe P and is assembled with a clamp 44 for gripping the pipe P. The clamp 44 is regulated by a guide pin 45 in the direction of displacement accompanying expansion and contraction of the diaphragm 43.

  In the head chuck 40 configured as described above, the diaphragm 43 is regulated so as to expand only in the inner surface direction of the outer case 41. For this reason, the range in which the clamp 44 is displaced in order to grip or release the pipe P can be a range within the outer dimension of the outer case 41. Therefore, the outer dimension of the head chuck 40 can be reduced.

  In the head chuck 40, the force (clamping force) for gripping the pipe P can be adjusted by appropriately changing the air pressure supplied to the diaphragm 43. That is, if the air pressure supplied to the diaphragm 43 is large, the clamp 44 is strongly pressed against the pipe P as the diaphragm 43 expands, so that the clamping force increases. On the other hand, if the air pressure supplied to the diaphragm 43 is small, the clamping force accompanying the expansion of the diaphragm 43 is small. Since the clamping force can be changed very easily in this way, the contact area between the clamp 44 and the pipe P necessary for gripping the pipe P with an appropriate clamping force, in other words, the axial direction of the head chuck 40 The dimensions can be reduced. Therefore, the head chuck 40 can hold the pipe P with an appropriate clamping force while being small.

  Next, the operation of the bending apparatus M configured as described above will be described in detail. To the bending apparatus M, a controller (not shown) whose main component is a microcomputer including a CPU, a ROM, a RAM, and the like is connected in order to comprehensively control the bending operation. When the operator inputs a command by operating the controller, the controller operates the cylinder 12, feed motors 22, 32, bending motors 25, 35, twist motors 26, 36, head cylinder 39, and head chuck 40, respectively. Control.

  For this reason, the operator inputs bending data including, for example, a feed amount, a twist amount, and a bending amount to the controller. Then, the operator supplies the pipe P, which has been cut in advance to the product length, to the bending apparatus M, and instructs the controller to start bending. In accordance with the command from the operator, the controller starts the operation of the bending apparatus M, and the bending apparatus M is configured to form a three-dimensional bent shape on the straight pipe P based on the input bending data. Control the operation. Hereinafter, the operation of the bending apparatus M controlled by the controller will be specifically described.

  When the controller acquires a command indicating the start of bending by the operator, the controller first causes the center chuck unit 10 of the bending apparatus M to grip the straight pipe P. That is, the controller extends the cylinder 12 to a position where the axis of the chuck mechanism 11 and the axis of the pipe P coincide. In this way, in a state where it matches the axis of the pipe P, the chuck mechanism 11 grips the outer periphery of the pipe P with the chuck claws. When the center chuck unit 10 grips the pipe P, the controller drives the feed motors 22 and 32 of the first bending unit 20 and the second bending unit 30, respectively, so that the processing units 20 and 30 are gripped. The pipe P is moved in the end direction.

  As described above, when the first bending unit 20 and the second bending unit 30 move to the end of the pipe P, the controller moves the processing units 20 and 30 in the direction of the center chuck unit 10 as shown in FIG. The operation is controlled so that a predetermined bent shape is processed in order toward the center of the pipe P (that is, toward the center of the pipe P). More specifically, the controller drives the feed motors 22 and 32 of the machining units 20 and 30 to move the machining units 20 and 30 by the feed amount represented by the input bending data. As a result, the bending dies 24 and 34 of the processing units 20 and 30 move to the positions where the pipe P is processed to bend, that is, the bending positions.

  Next, the controller drives the twist motors 26 and 36 of the processing units 20 and 30 to rotate the twist plates 27 and 37 around the axis of the pipe P by the amount of twist represented by the input bending data. In this way, the controller drives the bending motors 25 and 35 of the processing units 20 and 30 while the twist plates 27 and 37 are rotated by a predetermined amount around the axis of the pipe P, and the input bending processing data. The bending rollers of the bending dies 24 and 34 are rotated along the outer periphery of the fixed roller by the bending amount represented by

  As a result, it is possible to perform bending at a set bending position with a necessary twist amount (twist angle) and a necessary bend amount (bend angle) based on the input bending data. The controller repeatedly controls the operations of the first bending unit 20 and the second bending unit 30, that is, the moving operation, the twisting operation, and the bending operation, so that the processing units 20, 30 are The bending shape can be processed sequentially from the end toward the center chuck unit 10.

  By the way, when the first bending unit 20 and the second bending unit 30 sequentially process the bent shape from the end of the pipe P toward the center chuck unit 10, the gap between the center chuck unit 10 and the processing units 20, 30 is changed. The distance becomes smaller. Therefore, the controller reduces the head cylinder 39 of the second bending unit 30 as shown in FIG. 4 when the distance between the center chuck unit 10 and the processing units 20 and 30 is equal to or less than a preset distance. As a result, the bending die 34, the bending motor 35, and the twisting motor 36 that are integrally assembled to the support plate 38 are moved downward. Then, the bending die 34 is retracted from the axis of the pipe P. In this case, needless to say, the holding of the pipe P by the bending die 34 is released.

  Next, as shown in FIG. 5, the controller moves the second bending unit 30 to the bending position A where the second bending unit 30 was bent immediately before, more specifically, the end surface of the head chuck 40 is the bending end point at the bending position A. Move to the matching position. Then, the controller causes the head chuck 40 to grip the pipe P at the moved position. That is, the controller operates an air compressor (not shown) to supply air adjusted to a predetermined air pressure to the diaphragm 43 of the head chuck 40. Thereby, the diaphragm 43 expand | swells to the inner surface side of the outer case 41, and the clamp 44 assembled | attached to the diaphragm 43 pinches the pipe P with predetermined | prescribed clamping force. Next, the controller releases the gripping of the pipe P by the chuck mechanism 11 of the center chuck unit 10. Then, after releasing the grip of the chuck mechanism 11, the controller reduces the cylinder 12 and retracts the chuck mechanism 11 downward from the axis of the pipe P as shown in FIG. 6.

  As described above, in a state where the pipe P is gripped by the head chuck 40 and the chuck mechanism 11 is retracted from the axis of the pipe P, the controller continues a predetermined bending process for the first bending unit 20. Let That is, the controller also uses the bending data for the bending position of the first bending unit 20 beyond the center chuck unit 10, in other words, the bending position where the second bending unit 30 is originally bent. The first bending unit 20 is bent.

  Then, as the first bending unit 20 continues the bending process, the first bending process unit 20 and the second bending process unit 30 approach each other as shown in FIG. In this state, the head chuck 40 assembled to the second bending unit 30 approaches the bending die 24 of the processing unit 20 through the insertion hole 23a formed in the stand 23 of the first bending unit 20. . Therefore, the processing unit 20 can process a predetermined bent shape on the pipe P in the vicinity of the head chuck 40. As a result, the unbendable region can be substantially the sum of the axial dimension of the head chuck 40 and the distance L from the end surface of the bending die 24 to the bending center, as shown in FIG.

  As can be understood from the above description, according to the present embodiment, even when the first bending unit 20 and the second bending unit 30 are sequentially bent from the left and right ends of the pipe P, the unbendable region. Can be greatly reduced. Even in a state where the unbendable area is greatly reduced, the pipe P is satisfactorily gripped by the head chuck 40, so that accurate bending can be performed. Therefore, the bendable area can be expanded, the frequency of replacing the pipe P from the bending apparatus M to another bending apparatus (bending die) can be greatly reduced, and the productivity is greatly improved. be able to.

  In carrying out the present invention, the present invention is not limited to the above embodiment, and various modifications can be made. For example, in the above embodiment, after the support plate 38 of the second bending apparatus 30 is lowered, in other words, after the bending die 34 is retracted from the axis of the pipe P, the head chuck 40 is in the vicinity of the previous bending position. It carried out so that it might move to and may grasp pipe P.

  However, for example, according to the product shape of the pipe P such as a small number of bending processes, without moving the second bending unit 30 as described above, that is, in a state where the bending process at a certain bending process position is completed, It is also possible to implement such that the head chuck 40 grips the pipe P instead of the center chuck unit 10. According to this, since it is not necessary for the second bending unit 30 to move to a predetermined position, the time from the start to the end of bending for the pipe P (so-called cycle time) can be shortened. Therefore, productivity can be improved also in this case.

  Moreover, in the said embodiment, as mentioned above, the small head chuck 40 was assembled | attached with respect to the 2nd bending process unit 30, and it implemented. However, for example, a general-purpose chuck mechanism that has been widely used can be employed. In this case, when the first bending unit 20 and the second bending unit 30 approach each other, an insertion hole 23a formed in the stand 23 so that the chuck mechanism does not interfere with the first bending unit 20. Is formed large. According to this, although the bending apparatus is slightly increased in size, the unbendable region can be reduced as in the above embodiment. Therefore, the same effect as the above embodiment can be expected.

  Further, in the above embodiment, the chuck mechanism 11 of the center chuck unit 10 is implemented as a chuck mechanism employing a known structure. However, it goes without saying that the chuck mechanism 11 can be configured and implemented in the same manner as the head chuck 40.

It is the schematic which shows the structure of the bending apparatus which concerns on embodiment of this invention. FIG. 2 is a schematic cross-sectional view showing the configuration of the head chuck in FIG. 1. It is a figure for demonstrating the bending operation of the 1st and 2nd bending process unit in the state in which the pipe was hold | gripped by the chuck mechanism of a center chuck unit. It is a figure for demonstrating the operation | movement which the bending die of a 2nd bending process unit evacuates from on the axis line of a pipe. It is a figure for demonstrating the movement operation | movement of a 2nd bending process unit, and the holding position of the pipe by a head chuck. It is a figure for demonstrating retraction | saving operation | movement of a center chuck | zipper unit. It is a figure for demonstrating the positional relationship of the head chuck | zipper and the bending die of a 1st bending process unit in the state which the 1st and 2nd bending process unit contacted.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Center chuck unit, 11 ... Chuck mechanism, 20 ... 1st bending process unit, 21 ... Moving stand, 22 ... Feed motor, 23 ... Stand, 23a ... Insertion hole, 24 ... Bending die, 25 ... Bending motor, 26 ... Twist motor, 27 ... Twist plate, 30 ... Second bending unit, 31 ... Moving table, 32 ... Feed motor, 33 ... Stand, 34 ... Bending mold, 35 ... Bending motor, 36 ... Twist motor, 37 ... Twist plate, 38 ... Support plate, 39 ... Head cylinder, 40 ... Head chuck, 41 ... Outer case, 42 ... Inner case, 43 ... Diaphragm, 44 ... Clamp, M ... Bending device, P ... Pipe

Claims (3)

A chuck unit comprising a chuck mechanism capable of gripping a straight pipe and a retraction mechanism for retracting the chuck mechanism from the axis of the pipe, and provided on both sides of the chuck unit, the pipe has a predetermined bent shape. In a bending apparatus comprising a pair of bending units composed of a bending mechanism for bending and a moving mechanism for moving the bending mechanism connected via a support member in the axial direction of the pipe,
A head chuck mechanism that grips the pipe in response to retraction of the chuck mechanism of the chuck unit is provided for one of the pair of bending units.
Bending process characterized in that an insertion hole through which the head chuck mechanism is inserted is formed coaxially with the axis of the pipe with respect to the support member of the other bending unit of the pair of bending units. apparatus. In the bending apparatus according to claim 1,
Furthermore, a head retracting mechanism for retracting the bending mechanism from the axis of the pipe is provided for the one bending unit,
The one bending unit is
After the bending mechanism is retracted by the head retracting mechanism, the bending mechanism is moved by the moving mechanism in the direction of the bending position of the pipe that has been bent before retracting, and is moved to the vicinity of the bending position by the head chuck mechanism. And bending the pipe. In the bending apparatus according to claim 1 or 2,
The head chuck mechanism;
An outer case in which a cross-sectional shape perpendicular to the axial direction of the pipe is formed in a substantially U-shape;
A diaphragm that is housed in the outer case and expands and contracts according to the pressure of air supplied from the outside;
A bending apparatus comprising: a clamp that holds the pipe as the diaphragm expands and opens the pipe as the diaphragm contracts.

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